12 31 020 Removing and installing or replacing alternator (N54)

Necessary preliminary tasks:

NOTE: In order to remove the alternator, it is necessary to remove the AIR CONDITIONING COMPRESSOR .

In so doing:

Do not draw off A/C system refrigerant.
Do not detach refrigerant lines from A/C compressor.
Do not remove air conditioning compressor; instead, release from bracket only and place to one side.

Release screws (1).

Tightening torque 12 31 1AZ .

Release screw (2).

Tightening torque 12 31 2AZ .

Release screw (3) and remove with holder (4).

Tightening torque 13 31 2AZ .

Fig 1: Identifying Alternator Holder And Screws

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Unlock plug (1) and remove.

Remove protective cap (2) and release nut underneath.

Tightening torque 12 42 1AZ .

Remove battery positive lead (3).

Fig 2: Identifying Battery Positive Lead, Protective Cap And Plug

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NOTE: For purposes of improved clarity, graphics and description show A/C compressor removed.

Release screws (1) a few turns until bracket (2) is loose. Do not remove bracket (2).

Tightening torque 12 31 4AZ .

Feed out alternator (3) and remove.

Fig 3: Identifying Alternator Bracket And Screws

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Installation:

Modify deflection pulley (1) when replacing. To do so, release bolt under cover (2).

Tightening torque 12 31 3AZ .

Fig 4: Identifying Deflection Pulley And Bolt Under Cover

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Assemble engine.